Metagenomic analysis of taxonomic and functional changes in gut microbiota of patients with alcoholic dependence syndrome

Here we present the first metagenomic study of gut microbiota in patients with alcohol dependence syndrome (ADS) performed in the whole-genome (“shotgun”) format. Taxonomic analysis highlighted changes in community “drivers” abundance previously associated with inflammatory processes (including increase in Ruminococcus gnavus and torques, as well as decrease in Faecalibacterium and Akkermansia). Microbiota of alcoholics manifested presence of specific opportunistic pathogens rarely detected in healthy control subjects of the world. Differential analysis of metabolic potential basing on changes in KEGG Orthology groups abundance revealed increase in pathways associated with response to oxidative stress. Analysis of two specific gene groups – alcohol metabolism and virulence factors – also showed increase in comparison with the control groups. We suggest that gut microbiota distinct in alcoholics by both taxonomic and functional composition plays role in modulating the effect of alcohol on host organism.